Device for freezing foods



H. W. KLEIST DEVICE FOR FREEZING FooDs Aug. i3, 1946. 2,405,834

Filed-Dec. 29, 1941 5 Sheetsf-Sheet 1 .LNA

Aug@ 13 3946 H. w. KLEls-r 2,405,834

DEVICE FOR FREI'IZING FOODS i Filed Deo. 29, 1941 3 Sheets-Sheet 2 aF572' 39 3.9 V A 29 jerffzasn if jZezLvSt Aug. 13,L 1946.

H. w. KLEIST DEVICE FOR FREEzNG FooDs 3 sneets-sheet s Filed Dec. 29,1941 Patented Aug. 13, 1946 Unirse sr naar DEVICE Fon FREEZING Foonsration of Illinois Application December 29, 1941, Serial No. 424,741

2 Claims.

Ihis invention relates to devices for freezing foods and has for itsobject to provide a new and improved device of this description.

The invention has as a further object to provide a device for freezingfoods by means of conduction combined with air circulation. f

The invention has as a further object to provide a device for freezingfoods by means of which the time required for freezing is greatlyreduced.

The invention has further objects which are more particularly pointedout in the accompanying description. f

' Referring now to the drawings, Fig. 1 is a vertical sectional viewthrough one form of device embodying the invention;

Fig. 2 is a sectional view taken on line 2 2 of Fig'. 1;

Fig. 3 is a sectional view through a plate nipple for use in removingair from between the plates;

Fig. 4 is a view of one of the plates with a portion of one sheet brokenaway;

Fig. 5 is a view similar to Fig. 1 showing a modied construction, wherethe food is located in a separate freezing chamber.

Fig. 6 is a sectional View taken on line 6 6 of Fig. 4.

Like numerals refer to like parts throughout the several figures.

Referring now to the drawings, there is illustrated a cabinet orreceptacle I, provided with a plurality of refrigerating plates 2, 2a,2b, 2c, etc. These plates are vacuum plates and are`made up of `twocomparatively thin metal sheets 3 and 4. Located between these sheets isa pipe 5 formed into a coil. extending back and forth between thesheets. The sheets are hermetically sealed at the edges so as to form anair-tight receptacle. The pressure of the air on the inside of thisreceptacle ls reduced so that the greater external pressure causes thesheets'to make good heat conducting contact with the pipe 5.

For'this purpose, some means is provided by .means of which air may beremoved from between the sheets 3 and il. As herein shown, a nipple 'Iis provided which has a passageway 8 connecting with the interior of thespace between the sheets S and 13. There is a check valve 9 for closingthis passageway. Above the check valve 9 is an enlarged part ie whichhas an internal screw thread. An air removing device is connected withthis enlarged portion so that sufcient air may be withdrawn from betweenthe sheets 3 and il to secure the desired pressure Contact between thesheets 3 and l and the pipe 5. The check` valve 9 opens to permit theair to be withdrawn and closes when the air withdrawing device isdisconnected. There is` a plug H screwed into the nipple 'l which closesthe connection so as to prevent the air from entering,v thereby causingthe lower pressure within the plate to be maintained.

The above described structure is particularly advantageous for the useof plates partially filled with a eutect'ic solution. With referenceforexample to Figures 3 and 6, when the plug il is initially removed andthe ball raises, any suitable liquid may be poured into the plate spacethrough the passage 8 until the space between the plates is partiallyfilled. IThereafter the ball 9 or its' equivalent is positioned in placeand the space between the plates `which contains eutectic solution ispartially exhausted and the plug ll is returnedy in place; The ball 9then serves as a check valve preventing the entry of air into theevacuated interior of the plate.

The plates 2, 2a, 2b, etc., are mountedA in any desired manner. Asherein shown, these plates kare preferably mounted in a horizontalposition.

The plate 2 is preferably arranged at the top of thereceptacle. Theplates 2a, 2b, etc., are preferably arranged so that the food to befrozen may be placed on top of these plates. The plates `are alsopreferably arranged in staggered relation. There are spaces I2, I 2a,|2b, I2C, i242, etc., above the plates. These spaces are preferably ofdifferent heights to permit food material of different heights to beplaced therein and still have a space for the circulation of the coldair. These spaces are preferably arranged to form a continuouspassageway. The space l2 is connected at one end with the space l2a bythe opening i3; the space I2a is connected at the other end to the space|213 by the opening Hl; the space i211 is connected at its other end bythe opening i 5 with the space I2C; the space I2C is connected at itsother end by the opening I6 with the space i203; the space I2d isconnected by the opening il with the space I8; the space I8 is connectedby the opening l5 with the passageway 2G extending along one end of thereceptacle i and this passageway is connected to the space l2 betweenplates 2 and 2a by the opening 2l. An air moving device 22Vis preferablyarranged in the opening 2l and is operated by a motor 23. The passageway20 is bounded by the end wall of *he receptacle l and the plate 20a.

The plates 2, 2a, etc., are connected to a refrigerating apparatus 245of any of the usual types containing a compressor 25, a condenser 26 anda motor 2l for operating thefcoinpressor. A pipe 28 leads from thecondenser to one of the plates,

as for example, the plate 2. There is the usual expansion valve 29 inthis pipe. The pipe 23 connects with the pipe in the plate 2.

The pipes 5 in the different plates are connected together so that therefrigerant may pass through the pipes 5 in all of the plates. As hereinshown, these connections are made by the pipes 35, 3|, 32, 33, 34 and35.

There is preferably a storage compartment 36 separated from thereceptacle I and in which foods may be stored after they have beenfrozen. There is a plate 2f in this storage compartment and the pipe 5of this plate is connected by the pipe 35 to the pipe 5 in the plate 2c.The plate 2f is connected by pipe 31 with the compressor 25.

While the plates may be suspended in any desired manner, I have provideda simple, cheap and effective means for accomplishing this. In thisconstruction, one of the sheets of which each plate is made is largerthan the other so as to provide a projecting edge 3a. Angle irons 39 areplaced on the wall of the receptacle I and the plates are supported onthese angle irons by means of the projecting edges 3a (see Fig. 2).

The refrigerating apparatus 24 may be located in any place desired. Itwould ordinarily be located outside of the receptacle I and the storagecompartment 38 and would usually be located in the basement of thebuilding.

In Fig. 5 I have shown a modified construction. In this construction thecabinet I is provided with a plurality of refrigerating plates 2, 2a,2b, 2c, etc., with spaces between them, and an air moving device 22 tomove cooled air back and forth through the spaces between these plates.

These plates are connected to the refrigerating apparatus in the usualway, as shown in Fig. 1. This construction is particularly adapted foruse in connection with ice cream. The ice cream, in this case, is notfrozen or kept frozen on the plates, but is placed in the storagecompartment 36a.

In this construction, instead of having the cool air pass under theplate 2e, it is directed from the passageway IT through an opening 4I!in the partition 4I and passes into the freezing chamber or chambers 35aso that the material to be cooled therein is immersed in the cold airand this cold air then passes up through an opening 42 in the partitionl!! and thence along the passageway 20 back to the air moving device 22.By means of this construction the air is cooled to a very low degree asit passes between the plates and then this cold air, the temperature ofwhich may be below the freezing point, passes into the l freezingchamber so as to freeze the material therein. When it is such materialas ice cream, the ice cream can be kept at the proper desiredtemperature.

'I'he speed of the air moving device 22 may be varied to move the air ata slower or faster speed, depending upon the cooling condition desired.

By having the plates smooth, it is not necessary to defrost the deviceas very little Vfrost will deposit on the plates and Whatever doesdeposit can be easily and quickly scraped off while the refrigerant is`being passed through the plates.

By means of the air moving device the temperature in the freezingchamber may be reduced to from to 30 degrees below zero.

Access may be had to the receptacle I by means of doors 43 and accessmay be had to the storage chamber 35 or 36a by means of doors 44.

The operation of the invention isas follows:

When the device is to be used, the food to be frozen as shown in Fig. 1is placed on the plates 2a, 2b, 2c, etc. The refrigerant is circulatedthrough the pipes 5 of these plates by means of the refrigeratingapparatus 2a so as to cool the plates down below freezing. YThe airmoving device 22 is operated and the cold air is circulated back andforth between the plates and above the food thereon, and when it reachesthe bottom plate this cold air passes through the opening I9, up intothe passageway Ell and back to the air moving device 22.

'Ihe food is frozen by contact with the plates and is also frozen by thecold air striking the food as it is circulated by the air moving device22, In Fig. 5 the cooled air which is circulated between the plates isthen discharged into and circulated through the storage chamber 36a.

I have found that by means of the simultaneous cooperative action of thefreezing plates and the circulating cooled air the time required tofreeze the foods is decreased very materially, and I have found thisdecrease in freezing timel to be from 30 per cent to 50 per centdepending upon the food frozen.

After the foods are frozen they are removed from the plates and placedin storage chamber 3B, and other foods placed on the plates and frozen.This device, therefore, very greatly increases the efficiency infreezing foods by thus decreasing the time it takes to freeze the foodssoi-.hat a much larger quantity of food per day can be frozen and placedin the storage device. It is of course evident that a series of storagedevices may be used in order to take care of the food frozen on theplates in the receptacle.

By providing a clearance between adjacent plates which decreasesprogressively toward the air discharge end of the series of plates, Icause a progressive increase in the speed of movement of air between theplates, and also compensate for the volumetric change due to progressivecooling of the air. The use of the above described arrangementeconomizes on space. Small packages placed between the closer spacedshelves are more rapidly frozen, being subjected both tothe action ofthe plate on which they rest and to the action of the closely spacedshelf above.

I claim:

l. In a freezing and storage assembly for frozen foods and the like, aquick freezing compartment and means for quick freezing materialinserted therein, including a plurality of vertically spaced generallyhorizontal cold plates arranged in staggered relation and adapted toform, with the walls of said compartment, a devious path for air, eachsaid plate including upper and lower smooth surfaced metal sheets,whereby the passages defined between adjacent cold plates have smoothupper and lower walls, means for circulating a volatile refrigerantthrough said plates, and means, arranged to cooperate with said plates,for circulating air along the path defined by said plates, and anadditional storage chamber having an air passage connection adapted toadmit air from the quick freezing cabinet, and an air dischargeconnection adapted to return used air to the air circulating means.

2. In a freezing and storage assembly for frozen foods and the like, aquick freezing compartment and means for quick freezing materialinserted therein, including a plurality of vertically spaced generallyhorizontal cold plates arranged in staggered relation and adapted toform, with the walls of said compartment, a devious path for air, eachsaid plate including upper and c. 5 lower smooth surfaced metal sheetswhereby the passages defined between adjacent cold plates have smoothupper and lower walls, means for circulating a volatile refrigerantthrough said plates and means arranged to cooperate with said' platesfor circulating air along the path defined by said plates, and anadditional storage chami ber having an air passage connection adapted toHERMAN W. KLEIST.

